1. Field of the Invention
The present invention relates to an injection molding machine.
2. Description of the Related Art
An injection molding machine includes a cylinder that heats a molding material and a screw rotatably and reciprocatably provided in the cylinder. In a plasticizing process, the screw is rotated and the molding material is transferred toward in front of the screw. The molding material is gradually melted while being transferred forward. While the liquid molding material is being accumulated in front of the screw, the screw is moved backward by the pressure of the molding material in front of the screw. Thereafter, in a filling process, the screw is moved forward to inject the molding material reserved in front of the screw from the cylinder to be filled in a mold unit. The filled molding material is solidified to obtain a molding product in a cooling process. The molding product is exerted from the mold unit after a mold opening process. Generally, the plasticizing process is performed while the cooling process is being performed.